Determination of the Mineral Elements Present in Carrot Root (Daucus carota L.) Using Atomic Absorption Spectroscopy (AAS)
Yusuf Ismail Koleleni *
Department of Physics, Muslim University of Morogoro, P.O.Box 1031, Morogoro, Tanzania.
*Author to whom correspondence should be addressed.
Abstract
Carrot root (Daucus carota L.) is one of the most widely consumed root vegetables because of its high nutritional value and significant contribution to human health. Besides being an excellent source of provitamin A carotenoid, dietary fibre, and antioxidants, carrots also contain essential mineral elements such as potassium (K), calcium (Ca), magnesium (Mg), copper (Cu), and zinc (Zn), which are required for normal physiological functions including enzyme activation, bone development, electrolyte balance, and immune system regulation. The aim of this study was to determine the concentrations of selected mineral elements (K, Ca, Mg, Cu, and Zn) in carrot root samples using Flame Atomic Absorption Spectroscopy (FAAS). Fresh carrot samples were purchased from Kingalu Market in Morogoro Municipality and originated from the major carrot-producing regions of Tanzania, namely Arusha, Mbeya, and Morogoro. The samples were washed thoroughly with deionized water to remove external contaminants, oven-dried to constant weight, ground into fine powder, and digested using concentrated nitric acid and hydrogen peroxide following standard wet digestion procedures recommended for mineral analysis. The digested samples were analysed using a Flame Atomic Absorption Spectrometer (FAAS), a widely accepted analytical technique for determining trace and major mineral elements because of its high sensitivity, accuracy, and reproducibility. Calibration standards, reagent blanks, quality control samples, and replicate analyses were employed throughout the analytical process to ensure data quality and reliability. The measured mineral concentrations were statistically analysed and compared with internationally recognised nutritional guidelines and established food quality standards. The results showed that potassium was the most abundant mineral in all carrot samples, followed by calcium and magnesium, whereas copper and zinc were present in comparatively lower concentrations. Variations in mineral composition were observed among samples from different production regions, indicating the influence of soil characteristics, agronomic practices, and environmental conditions on mineral accumulation. Nevertheless, all analysed mineral concentrations were within acceptable nutritional ranges reported in previous studies and complied with international food quality standards. The study concludes that carrot roots consumed in Tanzania are valuable dietary sources of essential mineral elements and can contribute significantly to meeting daily mineral requirements.
Keywords: Carrot root, Daucus carota L., atomic absorption spectrometry, flame atomic absorption spectrometry, mineral composition, potassium, calcium, magnesium, zinc, copper, Tanzania, nutritional assessment